A problem which exists in contaminated areas is the poisoning of wildlife due to ingestion of contaminants contained in sediments. This invention proposes to prevent access to wildlife to contaminated sediments in wetlands and other areas when the sediment forms a part of the natural setting for the wildlife, e.g. feeding and/or resting area such as ponds. Usually this problem is dealt with by removing and treating the contaminated sediment, which destroys or severely alters the natural habitat.
Previous methods of keeping wildlife and contamination separated include the construction of landfill liners and caps; but this applies to locales where the contamination is confined to a few relatively limited, well defined areas (since it was transported to and concentrates at the site): in addition, the contaminated material and capping is at least partially above the water table. The above two methods of reducing wildlife exposure to contamination, namely--1) removal and treatment of the material and 2) the construction of landfill liners and caps, are quite expensive, more complicated than the proposed barrier of the present invention, and don't pertain in situations where the contaminated sediment may lie on the bottom of ponds or other feeding areas for wildlife.
A third possible method of keeping wildlife from exposure to contaminants is the placement of a thick fill or soil layer over the contaminated area. However, this method would be susceptible to erosion caused by water movements, and if it is not thick enough, would be damaged by movement of large animals (e.g. moose), which punch through the soil layer.
Geosynthetic materials, including geotextiles, (see ASTM D4439-91a) are commonly used to separate dissimilar soils; but, on information and belief, have not been used to separate soil and wildlife, when the soil is submerged at least part of the time.